Scarifier arrangement



March 29, 1966 w. w. KEUSDER 3,242,995

SCARIFIER ARRANGEMENT Filed June 27, 1963 3 Sheets-Sheet 1 o k Q I V \0 00 I T m INVENTOR.

WALTER W ksusoz/e A TTORNE Y March 29, 1966 w. w. KEUSDER SCARIFIER ARRANGEMENT 5 Sheets-Sheet 2 Filed June 2'7, 1963 d mm INVENTOR. [WA/.7272 W. /(EL/5D/Q A 77'0/2NEY March 29, 1966 w. w. KEUSDER 3,242,995

S CARIFIER ARRANGEMENT Filed June 27, 19 63 s Sheets-Sheet 5 I NVE NTOR.

United States Patent 3,242,995 SCARIFIER ARRANGEMENT Walter Wayne Keusder, 6420 Hedding St., Los Angeles, Calif. Filed June 27, 1963, Ser. No. 291,111 7 Claims. (Cl. 172-462) This invention relates to grooving and mixing machines, and more particularly, to an improved scarifier forming part of or for use with mobile road working vehicles to provide scarification of, for example, an asphalt pavement roadway.

In many road working operations it is often necessary to scarify the roadway as part of the over-all construction and maintenance procedures required thereon. For example, hotscarification is often required when reconditioning an asphalt pavement roadway having a surface layer of asphalt concrete. In such an operation, the surface layerof asphalt concrete is first heated and then scarified to provide an in-place mixing of the constituents of the asphalt concrete surface layer. The scarification generally comprises making a plurality of grooves in the roadway by a toothed member that not only provides the road-working machinery. This type of scarification breaks up the asphalt concrete surface layer into a plurality of comparatively small segments which are introduced into a mobile pug mill where they are ground and remixed before redepositing on the roadway surface.

In other applications, such as windrowing compost and combing surface areas of, for example, open mines, to accelerate surface drying, arrangements are often utilized to provide both a plurality of grooves to a preselected depth as well as mixing of the constituents.

Scarifiers utilized in the past in both hot and cold scarification as well as prior windrowing and combing arrangements have not always proven to be completely satisfactory. For example, in hot scarification, the scarifier is often coupled to the mobile vehicle containing the furnace hood that provides the heating of the surface to be scarified. Such hoods often may be laterally side shifted with respect to the direction of traverse of the vehicle, and, to provide proper scarification of the surface, the scarifier should also have the capability of being side shifted for alignment with the hood so that scarification takes place in the surface heated by the hood. Also,

.it is often desirable in scarification that the angle of incidence of the tooth members performing the scarification be substantially constant with respect to the plane of the surface being scarified regardless of the depth of scarifiication that is desired. It is generally preferred that the depth of scarification be constant across the width of the scarifier, regardless of vertical irregularities, such as a crowned roadway provides. Further, it is often necessary to raise and lower the scarifier with respect to the roadway surface so that the depth of scarification may be controlled and the scarifier lifted to avoid obstacles such as rocks, railway tracks, and the like.

The scarifiers utilized in the past have not always been able to achieve these desiderata. More particularly, the

prior art scarifiers have been comparatively fixed with respect to lateral shifting. Also, they have generally been raised and lowered in a vertical plane in arcu'ate ICE paths that vary the angle of incidence of the tooth members with respect to the roadway, depending upon the depth of scarification. No scarifier utilized in the past has been, according to the best of applicants knowledge, capable of providing substantially uniform depth of scarification on a crowned or other irregular or non-coplanar surfaced roadway.

Accordingly, it is an object of applicants invention to provide an improved surface grooving and mixing arrangement.

It is another object of applicants invention herein to provide a surface grooving and mixing arrangement that may be laterally shifted.

It is another object of applicants invention to provide an improved scarifier where-in the tooth members thereof may be maintained at substantially a constant angle of incidence with respect to the surface to be scarified, independently of the depth of scarification desired.

It is yet another object of applicants invention to provide a scarifier that will track the mobile vehicle pulling the scarifier along the surface.

It is another object of applicants invention to provide a scarifier that scarifies to a preselected depth independently of surface-irregularities or crowns in the surface to be scarified.

The above and other objects are achieved according to the broad aspects of applicants invention by providing a scarifier that is slidingly coupled to the back end of a mobile vehicle, which vehicle pulls the scarifier over the surface to be scarified. The scarifier may be side shifted laterally of the direction of travel of the vehicle on the sliding mounting of the scarifier on the vehicle by means of, for example, a hydraulic actuator. This permits lateral shifting of the scarifier so that it may closely follow the preselected heated path of a hood that may be carried on the mobile vehicle for heating the surface to be scarified.

The scarifier head which comprises a plurality of tooth .rnembers adapted to engage the surface to be scarified and to provide scarification thereof is coupled to a bottom portion of a frame member that is pivotally coupled to the portion of the scarifier slidingly coupled to the mobile vehicle. The pivotal coupling of the frame member allows vertical positioning of the scarifier head with respect to the surface to be scarified and it may be accomplished, for example, by a hydraulic actuator. In the preferred embodiment of applicants invention, a parallel four-bar linkage is provided for the vertical movement of the scarifier head so that the preselected angle of incidence of the tooth members with respect to the roadway is maintained regardless of the elevational differences between the tooth members and the roadway or the depth of scarification selected.

In another embodiment of applicants invention the scarifier head comprising the tooth members for scarification of a surface to be scarified is pivotally coupled to the frame member and movably connected to adjacent scarify ing heads to allow relative motion in a vertical plane thereof so that the tooth members in the scarifier head may conform, in segments, to a crowned or irregular surface road.

The above and other embodiments of applicants invention are explained in more detail in the following description, taken together with the accompanying drawings, wherein similar reference characters refer to similar elements throughout, and in which:

FIGURES 1, 2 and 3 illustrate one embodiment of applicants invention;

FIGURES 4, 5 and 6 illustrate another embodiment of applicants invention; and

FIGURES 7 and 8 illustrate another embodiment of applicants invention.

Referring now to FIGURES 1, 2 and 3, there is shown the structure associated with one embodiment of applicants invention. In this embodiment, a scarifier, generally designated 10, is coupled to a mobile vehicle 12 adapted to pull the scarifier in the direction of the arrow 14 over a surface 16 that is to be scarified.

The mobile vehicle 12 may be of any type desired. For example, in road-working equipment it may be similar to the mobile surface heater described in copending application Serial No. 291,110 filed on June 27, 1963, or may be of any type of machine. Where hot scarification is being performed, however, applicant prefers that the scarifier be coupled directly to the mobile vehicle, that includes the furnace hood for heating the surface 16 so that cooling of the surface 16 does not occur prior to scarification. However, Where cold scarification is desired, the mobile vehicle 12 may be of any variety. In addition, it will be appreciated that applicant improved scarifier may be utilized not only in road-working applications', but in any other applications where it is desired to provide a plurality of scarifications in a surface 16.

A pair of shafts 18 are coupled to the mobile vehicle 12. ats'the rear thereof and slidingly support the scarifier 10 thereon. The scarifier 10 has a first'frame, generally designated 20, comprising a pair of vertically-disposed support members 22 and transversely extending sleeve members 24 coupled to the vertically disposed support members 22 andengaging the transversely-disposed shaft members 18. The sleeve members 24 provide not only lateral and vertical rigidity to the first frame 20 but also slidingly retain the scarifier 10 on the transversely-disposed shafts 18.

Lateral shifting of the scarifier 10 in the direction indicated by the arrow 26 is achieved by utilization of the hydraulic actuator 28. The hydraulic actuator 28 is illustrated in greater detail in FIGURE 2. As shown thereon, the hydraulic actuator 2.8 is coupled to the vertical support members 22 by angle supports 30. The angle supports 30 are rigidly coupled to the cylinder 32 of hydraulic actuator 28. Thus, the cylinder 32 is rigidly coupled to the first frame 20. A piston 34 is contained within the cylinder 32 and'a shaft member 36 is coupled to the piston .34 and extends from cylinder 32 from both ends thereof.

The portions 36a and 36b of the shaft 36 are slidingly retained in brackets 33a and 33b of the mobile vehicle 12 by stops 35a and 35b, respectively.

Ports are provided on both sides of the piston 34, as for example ports 38a and 38b for inlet and discharge of hydraulic fluid. When pressurized hydraulic oil, for example, is fed into the hydraulic. actuator 28 through port 38a, the scarifier 10 is shifted laterally in the direction of the arrow 26a since the piston is coupled through the shaft portion 36a to the mobile vehicle 12 by engagement of stop 35a with bracket 33a. Similarly, when pressurized hydraulic oil is fed into the hydraulic actuator 28 through port38b, the scarifier 10 is laterally shifted with respect to the mobile vehicle 12 in the direction of the arrow 2612 since stop 35b engages bracket 33b. This double shafted hydraulic actuator arrangement is preferred by applicant since regardless of the directions of side shifting of the scarifier 10, a portion of the shaft 36 is maintained in tension and neither portion 36a nor 36b is subjected to compressive forces which might tend to distort them. The hydraulic actuator 28 may be of conventional design such as Parker-Hannifin hydraulic cylinder, model No. KC 2L-L-19, manufactured by Parker-Hannifin Corporation.

A plurality of link members 40 are pivotally coupled -.to the first frame 20 by pivot rods 42 and 42a arranged in a spaced relationship. A second frame member 44 is pivotally coupled to the link members 40 by pivot rods 46 and 46a and comprises a pair of vertically disposed support members 48 rotatably coupled to tube members 50 and 50a through which the pivot rods 46 are carried. The first frame 20, the link members 40 and the second frame 44 comprise a parallel four-bar linkage assembly such that vertical movement of the second frame 44 with respect to the first frame 20 maintains the second frame 44 substantially parallel to the first frame 20.

The second frame 44 is moved vertically toward and away from the surface to be scarified' 16, in a direction of the arrow 52 by the hydraulic actuator 54 pivotally coupled to an A-frame 56. The'A-frame 56 comprises side bars 58 .coupled, at their apex 60, to a fork 64 engaging the shaft 62 of hydraulic actuator 54.

The forward side bars 58 of the A-frame 56 are coupled to the lower tube member 50a of the second frame 44. A pair of rear support arms '69 of the A-frame 56 are rotatably mounted on the lower pivot rod 42:; of the first frame 20 and are coupled to-side bars 58 at the apex 60.

Extension of the shaft 62 from the hydraulic actuator 54 lowers the second frame 44 toward the surface 16. Similarly, retraction of the shaft-62 .into'the hydraulic actuator 54 raises the second frame 44 away from the surface 16. The hydraulic actuator 54 is pivotally coupled for vertical rotational movement to the first frame 20 by trunnion mount 65 so that raising and lowering of the second frame 44-may be achieved regardless of the position of lateral shifting of the scarifier 1'0 with respect to the mobile vehicle 12. v 7

It will be appreciated that since the fir'stframe20,"tlie link members 40 and the second frame 44 comprise a fourbar linkage, the second frame 44 moves substantially parallel to the first frame 20 duringv'ertical movement of the second frame 44 by the hydraulic actuator 54. Thus, while the second frame 44 may be moved inwardly and outwardly with respect to the first frame 20, regardless of the spatial separation of the second frame 44 from the first frame 20, it is retained in substantially parallel re lationship thereto.

A scarifier head 67 is coupled to the second frame 44 and moves therewith in both vertical and lateral directions. The scarifier head 67 has a plurality of teeth 71 that engage the surface 16 to provide scarificatiOnthereQf.

FIGURES 4, 5, and 6 illustrate the structure-associated with another embodiment of applicants improved scarifier. As shown thereon, there is a mobile vehicle 70 adapted to move in the direction of arrow 72 to pull the scarifier, generally designated 74, across a surface to be scarified 76. The mobile vehicle 70 may be similar to the mobile vehicle 10 described in the above embodiment of applicants invention. A first frame 78 of the scarifier 74 is slidingly mounted on shafts '80 of the mobile vehicle 70 by the sleeve members 82 in sliding engagement therewith, and the sleeve members 82 are coupled to vertical supports 98. The first frame 78 is adapted to move laterally of the mobile vehicle 70 in the directions indicated by the arrow 84.

In this embodiment lateral movement of the scarifier 74 is achieved by utilization of an electric motor 86 driving a pinion 88 engaging a track 90 coupled to the first frame 78.

The first frame 73 has upper arms 94 and lower arms 96 coupled to vertical supports 98 and extending away from the vehicle 70.-

A pair of hydraulic actuators 102,'eac'h comprising a cylinder 104 and a shaft 106 have the cylinders 104 thereof secured to the upper arms 94 of first frame 78 in spaced-apart relationship.

The shafts 106 of the hydraulic actuators 102 are coupled to a second frame 110 and the second frame 110 is raised and lowered with respect to the surface 76 to be scarified by the hydraulic actuators 102 in the direction of the arrow 108 and is stabilized for vertical movement by pins of arms 96 engaging slots 107 in second frame 110.

In this embodiment, applicant provides a segmented scarifier head. It will be appreciated that the segmented scarifier. head illustrated in this embodiment could equally well be used in the other embodiments of applicants invention described herein. Similarly, the electric motor 86 utilized to laterally move the scarifier 74 could also be utilized in the other embodiments of applicants in vention described herein.

The segmentedzscarifier head comprises a plurality of load bars 112, 114, and 116. Each of the load bars is movably coupled to the adjacent load bar. That is, outermost load bars 112 and 116 are movably coupled to the inner load bar 114. This arrangement applicant has found particularly useful in providing scarification on crowned roads and similar vertically irregular surfaces.

The inner load bar 114 is thus seen to be free-floating with respect to the second frame 110 through its movable coupling to the outer load bars 112 and 116.- The coupling of the outer load bars 112 and 116 to the inner load bar 114 isaccomplished by means of pins 118 coupled mean of the load bars 112 and 116 and engaging'slots 120 in the inner load bar 114 as illustrated in more retail in FIGURE 6. The length and shape of the slots120"determi ne the amount of relative movement between theouter load bars 112 and lll6and the inner load bar 114', there will be, and the amount of vertical deviation between the scarifier tooth supports122coupled to each of the load bars 112, 1,14, and 116.

Thus the inner loadbar 114 may be vertically raised with respect to the outer load bars 112 and 116 and through action of the pin and slot arrangement defined above, the outer load bars .112 and 116 rotate on their pivotalrnountings 124 by which they are coupled to the second frame member 110 to achieve the desired crown correction. It will be appreciated that any number of load bars may be utilized in the practice of applicants invention to provide even finer crown correction that is achieved, forexample, with the three load bars illustrated in FIGURE 5.

Applicant has also found that in many scarifying operations, it'is desirable to have a scarifier that will track the vehicle that is pulling the scarifier. This embodiment of applicants inventionis illustrated in FIGURES 7 and 8. As shown thereon, a mobile vehicle 130 which may be similar to the mobile vehicles and 70, described above, has a first frame 178 of attracking scarifier, generally designated 132, slidingly coupled thereto on shafts 134 of the mobile vehicle by sleeves 136. This mountingof the tracking scarifier 132 on the mobile vehicle 130 is similar to the mounting of the scarifier 74 on the mobile vehicle 70 and the scarifier 10 on the mobile vehicle 12- described above.

The sleeves 136 are coupled to a pair of vertically disposed support brackets 138 which are maintained in spaced relationship thereby. A plate 140 is also coupied to the brackets 138 and a pair of shaft supports 142 are coupled to the plate 140 and extend therefrom. The shaft supports 142 have aligned shaft receiving apertures 146 therein for receiving a shaft 148 which is retained therein by stops 150 secured to the shaft 148. The stops 150 prevent the shaft 148 from separating from the shaft supports 142 during actuation of the hydraulic actuator 152 as described below.

A plurality of links 156 are pivotally coupled for vertical pivotal movement in the shaft 148 by pivot pins 158. Thus the links 156' are free to rotate on the pivot pins 158 in a vertical plane but rotate with the shaft 148-in horizontal planes and also move translationally in lateral directions as indicated by the arrow 160 with -movement ofthe shaft 148 in lateral directions.

The links 156 are also pivotally coupled to a second frame 164 by pivot pins 162. The second frame 164, the shaft 148 and the plurality of links 156 define a parallel four-bar linkage so that vertical movement of the second frame 164 as indicated by the arrow 166 maintains the second frame 164 substantially parallel to the shaft 148. Thus, the angle of incidence of the tooth members 170 with respect to the surface to be 6 scarified 172 is maintained substantially constant regardless of the vertical positioning of the second frame 164.

The second frame 164 is raised and lowered with respect to the surface 172 by,means of the hydraulic actuator 152 pivotally coupled to a clevis 174 secured to the shaft 148, and rotatingtherewith. Therefore, the hydraulic actuator 152 rotates in a horizontal plane with rotation of the shaft 148. Theshaft. 1800f thehydraulic actuator 152 is pivotally coupled to an A-frame;176 which may be similar tothe, A-frame. 56; described above in connection with the embodiment of Y applicants; invention shown in FIGURES 1, 2, and' 3. The A-frame. 176.; is in this embodiment, coupled to the lowermost pair of links 156 which are pivotally.coupledrtotboth'theframe 164 and theshaft 1.48 by the lowermostrpivotpins 162 and158, respectively, sosthat rotationofthefeframe 176 with respect,' to the: frame 164 and the shaft. 1.48 is allowed toprovide the vertical positionirigofitheframe 164 by actuation of hydraulic .actuator;152.

Lateral positioning of the scarifier. 132-: with respect to the mobile vehicle in the: direction. of. the; arrow 166 isachieved, in this embodiment'of applicantisinvention, by forcesacting on the scarifiertoothmembers 170 in lateral directions as indicated by; arrow. v when the tooth members 170.- are engaged in. the surface tov be scarified 1721 Thus, for example, when the'vehicle 130 turns, forces will be actinglaterally. on. the. scarifier. tooth members 17,0..as it is dragged: through the: surface. 172 by the vehicle.130. This initially causesza rotation of the shaft 148; in the shaft supports142 an'dithe; lateral force is then transmitted through the shaft. 148: to the shaft supports 142' which moves the frame 1.78 in lateral directions, as indicated bLyzthearrow 16.0.; Lateraltmovementof the first frame 178-wil1.continue: until alignment of the first frame. 178 andthe second frame 164 is achieved so that. lateralLforces. are no longer, transmitted therebetween.

The three embodiments. of applicants. invention shown herein. illustrate some of the manywvariations. and adaptions of applicants invention. Various features illus trated on one of. the three embodiments may, ofcourse, be utilized. interchangeably in. the: others. As noted above, the segmentedscarifier head shown. on FIGS. 4, 5 and 6 could equally well. beutilized in the-embodiment shown on FIGS. 1, 2 and 3 and in the .embodimeritshown on FIGS. 7 and 8. i

This concludes the description of applicants invention herein. It will be appreciated that many modifications and variations of applicants. invention may be achieved by those. skilled'in the art. Therefore, the following claims. are intended. to cover allsuch variations and adaptations falling within the true scope and spirit of applicants invention.

I claim:

1. An improved scarifier of the, type adapted to be moved along a surface to be scarified by a mobile vehicle comprising, in combination:

afirst frame member slidin-gly mounted on said mobile vehicle and adapted to be moved laterally of said vehicle; i

means for moving said first frame member laterally of said mobile vehiclej a second frame member;

a plurality of link members having first ends mounted for pivotal motion with respectto saidi first frame member and second ends pivotally coupled tosaid second frame member to permit relative raising and lowering of said second frame member with respect to said first frame member, and said second frame member moving laterally with said lateral movement of said first frame member;

a scarifier head coupled to said second'frame member and having tooth members adapted to engage the surface to be scarified;

means coupled to said second frame member for raising and lowering said second frame member relative to first frame member to selectively move said tooth members in engagement with and disengagement from the surface to be scarified; and

means for maintaining said scarifier tooth members in engagement with the surface to be scarified at a preselected force.

2. An improved scarifier comprising, in combination:

a first frame member slidingly mounted on a mobile vehicle for lateral movement thereof relative to the direction of travel of said mobile vehicle;

a first hydraulic actuator for laterally moving said first frame member and comprising a cylinder, a piston in said cylinder and a shaft coupled to said piston and having a first portion extending from a first end of said cylinder and a second portion extending from a second end of said cylinder, said cylinder secured to said first frame member, and said first portion and said second portion of said shaft coupled to the mobile vehicle;

a second frame member;

a plurality of link members pivotally coupled to said first and said second frame members to define therewith a parallel four-bar linkage;

a second hydraulic actuator for raising and lowering said second frame member and comprising a cylinder and a shaft extending therefrom, said cylinder of said second hydraulic actuator pivotally coupled to said first frame member and said shaft of said second actuator pivotally coupled to said second frame member; and

a scarifier head having tooth members adapted to engage a surface to be scarified and coupled to said second frame member whereby raising and lowering said second frame member selectively disengages and engages said scarifier tooth members with said surface to be scarified.

3. An improved scarifier of the type adapted to be moved along a surface to be scarified by a mobile vehicle comprising, in combination:

a first frame member slidingly mounted on a mobile vehicle for horizontal movement relative thereto in directions substantially perpendicular to the direction of travel of the mobile vehicle over the surface to be scarified;

means coupled to said first frame member and to said mobile vehicle for horizontally moving said first frame member;

a second frame member spaced apart from said first frame member and adapted to be moved horizontally with said first frame member and towards and away from the surface to be scarified;

a plurality of link members pivotally coupled to said first frame member and said second frame member and defining a parallel four-bar linkage therewith;

an A-frame having the cross-bar thereof pivotally coupled to said second frame member;

a hydraulicactuator comprising a cylinder and a shaft, said cylinder pivotally coupled to said first frame member and said shaft pivotally coupled to the apex of said A-frame for raising and lowering said second frame member with respect to said first frame member and substantially parallel thereto;

a scarifier head having a plurality of tooth members for engaging the surface to be scarified; and

means for maintaining said tooth members in engage ment with the surface to be scarified at a preselected force.

4. An improved scarifier of the type adapted to be moved along a surface to be scarified by a mobile vehicle comprising, in combination:

tion of travel of the mobile vehicle over the surface to be scarified;

first motion producing means coupled to said first frame member and said mobile vehicle for horizontally moving said first frame member;

a second frame member having a plurality of transversely-extending load bars pivotally coupled thereto and each of said plurality of load bars movably coupled to the adjacent load bar for relative motion in a vertical plane;

a plurality of scarifier heads, each of said plurality of scarifier heads coupled to one of said load bars for motion in a vertical plane therewith and each of said plurality of scarifier heads having a plurality of tooth members adapted to engage a surface to be scarified; and

second motion producing means coupled to said first frame member and said second frame member. for moving said second frame member towards and away from the surface to be scarified to move said tooth members in engagement with and disengagement from the surface to be scarified.

5. An improved scarifier of the type adapted to be moved along a surface to be scarified by a mobile vehicle comprising, in combination:

a first frame member slidingly mounted the back end on a mobile vehicle for horizontal movement relative thereto in directions substantially perpendicular to the direction of travel of the mobile vehicle over the surface to be scarified;

a second frame member having a plurality of trans versely-extending load bars pivotally coupled thereto and each of said plurality of load bars movably coupled to the adjacent load bar for relative motion in a vertical plane;

a plurality of scarifier heads, each of said plurality of scarifier heads coupled to one of said load barsfor motion in a vertical plane therewith and each of said plurality of scarifier heads having a plurality of tooth members adapted to engage a surface to be scarified; and 4 motion producing means coupled to said first frame member and said second frame member for moving said second frame member substantially parallel to said first frame member and towards and away from the surface to be scarified to move said tooth members in engagement with and disengagement from the surface to be scarified.

6. An improved scarifier comprising, in combination:

a first frame member slidingly mounted on a mobile vehicle for lateral movement thereof relative to the direction of travel of said mobile vehicle; I p

a first hydraulic actuator for laterally moving said first frame member and comprising a cylinder, a pistonin said cylinder and a shaft coupled to said piston and having a first portion extending from a first end of said cylinder and a second portion extending from a second end of said cylinder, said cylinder secured to said first frame member, and said first portion and said second portion of said shaft secured to the mobile vehicle;

a second frame member vhaving a plurality of transverselyexteuding load bars pivotally coupled thereto and each of said plurality of load bars movably coupl ed to the adjacent load bar for motion in a vertical plane; i

a plurality of scarifier heads, each of said plurality of scarifier heads coupled to one of said load barsfor motion in a vertical plane therewith, each of said plurality of scarifier heads having a plurality of tooth members adapted to engage a surface to be scarified;

a plurality of link members pivotally coupled 'to said first and said second frame members to define therewith a parallel four-bar linkage; and

a second hydraulic actuator for raising and lowering said second frame member and comprising a cylinder and shaft extending therefrom, said cylinder of said second hydraulic actuator pivotally coupled to said first frame member and said shaft of said second actuator pivotally coupled to said second frame member.

7. An improved scarifier comprising, in combination:

a first frame member slidingly mounted on a mobile vehicle for lateral movement thereof relative to the direction of travel of said mobile vehicle;

a first hydraulic actuator for laterally moving said first frame member and comprising a cylinder, a piston in said cylinder and a shaft coupled to said piston and having a first portion extending from a first end of said cylinder and a second portion extending from a second end of said cylinder, sai-d cylinder secured to said first frame member, and said first portion and said second portion of said shaft secured to the mobile vehicle;

a second frame member;

a plurality of link members pivotally coupled to said first frame member and said second frame member and defining a parallel four-bar linkage therewith;

an A-frame having the cross-bar thereof pivotally coupled to said second frame member;

a second hydraulic actuator for raising and lowering said second frame member comprising a cylinder and a shaft, said cylinder pivotally coupled to said first 10 frame member and said shaft pivotally coupled to the apex of said A-frame;

a scarifier head having tooth members adapted to en gage a surface to be scarified and coupled to said second frame member whereby raising and lowering said second frame member selectively disengages and engages said scarifier tooth members with said surface to be scarified; and

means for maintaining said tooth members in engagement with the surface to be scarified at a preselected force.

References Cited by the Examiner UNITED STATES PATENTS 976,729 11/1910 Ellett 172-742 X 1,495,277 5/ 1924 Thompson 172464 X 2,110,790 3/1938 Daugherty et al. 172-438 X 2,653,795 9/ 1953 Reeves.

2,733,646 2/1956' Sheffield 17230 7 X 3,019,923 2/1962 Morrison et a1. 172-667 X FOREIGN PATENTS 81,068 2/ 1950 Norway.

25 ANTONIO F. GUIDA, Primary Examiner.

T. GRAHAM CRAVER, A. G. STONE, Examiners.

.T. R. OAKS, Assistant Examiner. 

1. AN IMPROVED SCARIFIER OF THE TYPE ADAPTED TO BE MOVED ALONG A SURFACE TO BE SCARIFIED BY A MOBILE VEHICLE COMPRISING, IN COMBINATION: A FIRST FRAME MEMBER SLIDINGLY MOUNTED ON SAID MOBILE VEHICLE AND ADAPTED TO BE MOVED LATERALLY OF SAID VEHICLE; MEANS FOR MOVING SAID FIRST FRAME MEMBER LATERALLY OF SAID MOBILE VEHICLE; A SECOND FRAME MEMBER; A PLURALITY OF LINK MEMBERS HAVING FIRST ENDS MOUNTED FOR PIVOTAL MOTION WITH RESPECT TO SAID FIRST FRAME MEMBER AND SECOND ENDS PIVOTALLY COUPLED TO SAID SECOND FRAME MEMBER TO PERMIT RELATIVE RAISING AND LOWERING OF SAID SECOND FRAME MEMBER WITH RESPECT TO SAID FIRST MEMBER, AND SAID SECOND FRAME MEMBER MOVING LATERALLY WITH SAID LATERAL MOVEMENT OF SAID FIRST FRAME MEMBER; A SCARIFIER HEAD COUPLED TO SAID SECOND FRAME MEMBER AND HAVING TOOTH MEMBERS ADAPTED TO ENGAGE THE SURFACE TO BE SCARIFIED; MEANS COUPLED TO SAID SECOND FRAMEMEMBER FOR RAISING AND LOWERING SAID SECOND FRAME MEMBER RELATIVE TO FIRST FRAME MEMBER TO SELECTIVELY MOVE SAID TOOTH MEMBERS IN ENGAGEMENT WITH AND DISENGAGEMENT FROM THE SURFACE TO BE SCARIFIED; AND MEANS FOR MAINTAINING SAID SCARIFIER TOOTH MEMBERS IN ENGAGEMENT WITH THE SURFACE TO BE SCARIFIED AT A PRESELECTED FORCE. 